Canfield Brothers Nimble 9 Boost Build5

Stretch it and Boost it. That could be the mantra of 2017 as many companies continue to update existing models. Those updates often include the switch to Boost 148mm rear spacing as well as “modern” geometry which typically features longer reach and front center measurements to compliment shorter stems and wider bars.

But as Canfield Brothers shows, those updates aren’t just for full suspension bikes. To create the fourth generation of their steel 29er, the Nimble 9 morphs into a more capable machine, and even adds a bit of plus compatibility…

Canfield Brothers Nimble 9 Boost Build-41
All photos c. Canfield Bros.

Canfield Brothers Nimble 9 Boost Build-74 Canfield Brothers Nimble 9 Boost Build-63

Billed as a 29″ all mountain hard tail, the 4130 chromoly frame couples a 66.5 degree HTA with super short 16.25″ (412.75mm) chainstays in the shortest position (16.9″ in longest position). The sliding 148 x 12 dropouts include an axle and allow the frame to run both geared and single speed drivetrains. Along with a longer reach, the frame gains a shorter seat tube for better dropper seat post clearance for shorter riders or the ability to run longer droppers for taller riders.

Nimble 9 2017 geometry


Plus compatibility doesn’t seem to be the focus, but Canfield Bros. point out that the frame can run up to a 27.5 x 2.8″ tire on a 35mm internally wide rim. Otherwise, a 29 x 2.5″ tire should fit.

Canfield Brothers Nimble 9 Boost Build-52

Up front, the 44mm headtube will accept tapered steerers and is meant for 120-140mm travel forks. Frames are kept simple with external cable routing and threaded 73mm bottom bracket shells, front derailleur compatibility, and IS brake mounts.

Canfield Brothers Nimble 9 Boost Colors6

Nimble 9 Boost frames will be available in 4 sizes and 4 colors starting at $749 for the frame only. From there, any combination of parts can be purchased from Canfield Bros. to create a partial or a full build. Available now.

Nimble 9 Boost Features:

● 29″ All Mountain

● 4130 chromoly steel

● Increased reach and shorter seat tube

● 66.5° head angle (w/ 140mm fork)

● Custom sliding Boost 148mm x 12mm rear dropouts, axle included

● Adjustable 16.25“ – 16.9” chainstays

● Singlespeed-able

● Stealth cable routing

● Sparkle metallic painted finish

● ED Black treated for superior anti-corrosion resistance

● Removable direct mount front derailleur block

● Two water bottle bosses


  1. Ya know, the Canfield brothers are on their game. This is a dream bike for down right fun and climbs great and DH’s even better. All similar frames are running a 68º HT. In the past I was not down w/ 29er, now it’s the best w/ all these trail versions out. Where I live it’s steep up and down but not overly rocky… perfect for a hardtail beast like this.

  2. This is a cool and innovative bike that helped create the long-low-short chain stay trend, i.e., it has been imitated by Kona, Trek and others. It takes the best of new standards- tapered headtube and Boost- and combines them with the best old ways of doing things: threaded bb’s and external cabling. However, beware one thing: the frame is heavy, around 6.5lbs as I recall. Hopefully the newer ones are lighter… Their Yelli Screamy has the same geo but is available in aluminum for not much more money.

    • Imitated? They’re adding their own gimmicks with that uselessly curved seat tube that’s doing nothing where the curve is, they could have easily had a straight tube that’s equally slack. The Trek has much shorter stays and much more tire clearance. These guys still aren’t the first. I’ve seen much older, custom fat bikes with lifted stays to shorten them far shorter than this bike, along with a curved seat tube that actually follows the line of the tire with barely any clearance if you don’t back the wheel up.

      • As I recall, the first Canfield Bros. hardtails came out around 2010, although I could be mistaken. Adding gimmicks doesn’t change the fact that Canfield pushed that type of geometry before it became popular. So a few people had custom bikes with that geometry bikes. Still, it was an isolated phenomenon. Canfield might not have been the first, but it was one of the first who pushed that formula explicitly.

  3. I have the EPO, steel is the way to go for modern day hardtail. Everyone has followed CB, the company is the best to deal with, you can’t even call Kona up on the phone.

COMMENT HERE: (For best results, log in through Wordpress or your social media account. Anonymous/fake email comments may be unapproved or deleted. ALL first-time commenter's posts are held for moderation. Check our Comment Policy for full details.)

This site uses Akismet to reduce spam. Learn how your comment data is processed.